7 Fascinating Facts About the Halogen Group in Chemistry That You Might Want to Know

• Fluor can react with noble gases. For example, with Xenon: 2Xe + 3F2 --> 2XeF3

• Some roles of Fluor The leaves of certain plants contain Fluor, making them highly toxic. One such compound, potassium fluoracetate (FCH2COOK), can kill a sheep with just 1g of the leaves containing it!

  However, Fluor does benefit humans. If you've heard advertisements for toothpaste, you'll know about this element, as it helps prevent cavities. But be cautious, as excessive amounts can be harmful! Your teeth might turn discolored!
  Additionally, Teflon, a synthetic polymer, can withstand temperatures up to 300°C and is completely non-conductive.

  In industry, Fluor is used to separate Uranium-235 isotopes from the naturally occurring Uranium-238, providing fuel for the nuclear industry.

  • Some compounds of chlorine and fluorine are harmful to the environment, especially in destroying the ozone layer. Chlorofluorocarbons (CFCs), used in refrigeration, are a prime example, though they are now restricted.

• Fluor was discovered in 1771 by Swedish chemist Carl Wilhelm Scheele, who reacted fluorite (CaF2) with sulfuric acid. Fluo in Latin means flowing, and it was later renamed Fluor, derived from the Greek meaning destruction, death.

• Chlorine was discovered in 1774, also by Scheele, when he reacted hydrochloric acid with the mineral pyrolusite (MnO2). The name Chlorine comes from the Greek word for yellow-green.

• Bromine was discovered in 1825 by French chemist Antoine Jerome Balard. The name comes from bromo in Greek, meaning stinky.
• Iodine was discovered in 1811 by French chemist Bernard Courtois. The Greek word iodes means purple.
• Astatine was discovered in 1940 by Italian physicists D. Corson, C. Mackenzie, and E. Segre. Its name comes from the Greek for unstable, which makes sense as it is a radioactive element!

Chlorine is a toxic chemical that can cause poisoning when inhaled or ingested. Upon entering the body, chlorine reacts with water to form hydrochloric acid (HCl) and hypochlorous acid (HClO), both of which are harmful to humans. Chlorine gas is commonly used to disinfect swimming pools and municipal water supplies, but this doesn't pose significant danger to humans in those contexts.

The main cause of chlorine poisoning occurs when individuals ingest cleaning products or mishandle chlorine in laboratory settings. Symptoms of poisoning affect the entire body. The digestive system is affected by burning sensations in the mouth, throat swelling, and vomiting. The respiratory system suffers from difficulty breathing and fluid accumulation in the lungs. The circulatory system may experience low blood pressure, skin damage, and an imbalance in blood pH. If inhaled, the victim should be moved to fresh air immediately. If swallowed (unless vomiting or convulsions occur), give milk or water.

Due to its dangerous nature, chlorine was used as a chemical weapon during warfare. During World War I, Germany and Britain used over 125,000 tons of chlorine gas. The German forces used chlorine to wipe out two French and Algerian divisions, with victims experiencing severe pain in their necks and chests.

Despite its hazardous properties, chlorine does not usually exist as a pure element but rather in compounds, with the most common being table salt (NaCl) that we use daily.

Indeed! The discovery of free fluorine (in its elemental form) is also a tale of danger and sacrifice by many scientists. Humphry Davy failed in his attempt to electrolyze hydrofluoric acid (HF) and was poisoned, although he did manage to determine that fluorine's atomic mass was 19.06.

In 1834, Davy's student, physicist Michael Faraday, tried to resolve the issue of isolating free fluorine by electrolyzing molten fluoride salts but also met with failure.

Later, the Knox brothers from Ireland conducted experiments for five years, resulting in one death and the other severely injured. Other scientists also shared the same fate as the Knox brothers.

It wasn't until 1854-1856 that French professor E. Fremy, from the École Polytechnique in Paris, succeeded in electrolyzing molten calcium fluoride (CaF2). Calcium metal appeared at the cathode, and a gas was released at the anode. Unfortunately, he was unable to collect the gas for further research on its properties.

In 1869, British chemist G. Gore managed to isolate a small amount of fluorine, but it exploded violently when reacting with hydrogen (due to fluorine's highly reactive nature, even in darkness!).

The final success in isolating free fluorine came from French scientist Henri Moissan in 1886, in the latter half of the 19th century! The following year, he successfully produced liquid fluorine. During his experiments, he had to wear a platinum armor suit, as platinum was one of the few metals resistant to fluorine's corrosive effects.